3 ms·
> Running an AVX2 workload we were expecting much higher power consumption but at under 500w for 128 threads, this is excellent. eish
by rb808 9y ago
> Running an AVX2 workload we were expecting much higher power consumption but at under 500w for 128 threads, this is excellent.
eish
- revelation 9y agoGranted the AVX2 performance of the Zen processors is intentionally crippled. It's more of a software compatibility implementation than actual performance boost.
- Recurecur 9y agoCitation?
- revelation 9y agoAgner on microarchitecture [1], page 213, another mention as a bottleneck on page 216: The Ryzen supports the AVX2 instruction set. 256-bit AVX and AVX2 instructions are split into two µops that do 128 bits each. AVX2 increased register width from 128-bit (AVX) to 256-bit, yet Ryzen cores can only process them 128-bit at a time. There is more to AVX2 than just width but that means in comparison to Intel processors, which can do the full 256-bit in a µop, the Ryzen throughput will suffer in tests that heavily emphasize AVX2 instructions (think video encoding). 1: http://www.agner.org/optimize/microarchitecture.pdf http://www.agner.org/optimize/microarchitecture.pdf
- Recurecur 9y agoThanks!